Like the Tin Man, rheumatoid arthritis sufferers might benefit from a little oil for their creaky joints. A diet high in fish oil and low in saturated fats, already known to help hearts, appears to lessen joint pain and stiffness.

At Albany Medical College in New York, 17 arthritis patients ate red meat only twice a week, dining mainly on skinless chicken, fish, skim milk, low-fat cheese and other low-fat fare. They also got a daily supplement of fish-oil capsules rich in eicosapentaenoic acid (EPA), the polyunsaturated fat that has been linked to several health benefits. A control group ate American--lots of meat, whole dairy products--and got placebos.

Our bodies make prostaglandins from dietary fats, notes Kremer. From saturated fat, though, we produce a type of prostaglandin that helps clot blood and inflame injured areas. From EPA, found in salmon and mackerel and other northern ocean fishes, we make prostaglandins that thin the blood and produce less inflammation. These blood-thinners also help prevent heart attacks. EPA-derived leukotrienes reduce inflammation, too.